1) Fusion requires extremely high temperatures to begin because ____. A) positive nuclei repel each other B) nuclei without neutrons can't create larger nuclei that DO contain neutrons C) hydrogen and helium are gases D) releasing more energy requires a greater input of energy first E) electrons interfere with the process 2) A nucleus of Uranium-235 nucleus of U-235 undergoes alpha decay. Write the decay equation for that reaction. 3) A nucleus of Th-231 undergoes beta decay. Write the decay equation that explains this